Programa Y Metodologia Toma De Muestras Analisis Aceite Usado

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  • Excelente información para arrancar un programa predictivo de análisis de aceites, recomendado.
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Programa Y Metodologia Toma De Muestras Analisis Aceite Usado

  1. 1. ™ Monitor THE COMPLETE GUIDE TO FLUID ANALYSIS Table of Contents What is Monitor™? ............................................................................................ 2 Lube Sampling Kits .......................................................................................... 4 Lube Samples .................................................................................................... 6 Bottle Labels ...................................................................................................... 7 Monitor™ Reports .............................................................................................. 8 How to Read the Report .................................................................................. 9 Sampling Instructions .................................................................................... 11 How to Sample ................................................................................................ 13 Technical Notes ................................................................................................ 14 Spectrometric Metals ................................................................................ 14 Fuel Contamination .................................................................................. 16 Soot Contamination .................................................................................. 17 Water Contamination .............................................................................. 18 Viscosity ...................................................................................................... 19 Additives .................................................................................................... 20 Neutralization Numbers .......................................................................... 23 Drain Interval Evaluation ........................................................................ 25 Particle Counting ...................................................................................... 27 Infrared Analysis ...................................................................................... 29 How Do I Interpret the Data? ................................................................ 31 Diesel Fuel Test Descriptions ..........................................................................34 Coolant Analysis Service ..................................................................................36 What is Monitor C™ ? ..................................................................................36 Coolant Sampling........................................................................................36 Sample Identification..................................................................................36 Interpreting Results ....................................................................................36 pH ..........................................................................................................36 % Glycol and Freeze Point..................................................................36 % TDS ....................................................................................................37 Liner Pitting ..........................................................................................37 Corrosion Products ..............................................................................37 Silicate Levels........................................................................................37 Buffers ....................................................................................................37 Sample Monitor - CTM Report ............................................................38 COMPASS ..........................................................................................................39 HORIZON ..........................................................................................................40 1
  2. 2. ™ Monitor LUBRICANT ANALYSIS SERVICE WHAT IS MONITOR ? TM Monitor™ Analysis is a service provided by Fleetguard through dealers to individuals or companies. The user removes the lube sample to be analyzed and submits sample direct to an independent laboratory to be analyzed. The laboratory will then report direct to the user or company that submitted the sample. A copy of each report is directed to the selling dealer. Monitor™ provides Product Support when used as an Equipment Management Tool. It is WHY A LUBE a Preventive Maintenance – Diagnostic Tool which is a picture of the internal condition ANALYSIS PROGRAM? of a component or system without disassembly. The Objective of Lube analysis is to maximize potential equipment reliability by: • Finding minor problems so that minor repairs can be made before they become major failures • Increasing UpTime with shorter repair times and preventing unscheduled downtime • Pointing out oversights in maintenance programs so corrections can be made • Scheduling of downtime for maintenance and repairs, thus preventing the schedule being determined, by equipment failures To achieve the desired objective, a lube analysis program must establish a TREND for each component sampled. All lube analysis programs like Monitor™ are designed to be a TREND analysis which is regularly scheduled (periodic) lube samples over a span of time. A TREND is a unique history over a period of time of what is happening to a unit in its application. TREND LUBE ANALYSIS A TREND requires at least three samples: 1st Sample is of Some Value - A Reference Point One sample can be a basic diagnosis of a condition that exists, but not a cause of Failure. 2nd Sample is of More Value - 3rd Sample is of Great Value - TREND established With a TREND established, continuing the periodic samples tracks the unit’s condition and gives an early Alert to problems. The span of time between the samples should be consistent to see a True Trend. The Lab Report history will show two types of Trends: • Drain Interval TREND - when the lube sample is only taken just prior to a lube change. The test data will be fairly consistent when the Time on the lube is nearly the same for each sample from a good system. This is the normal TREND for engines with frequent lube drains. • Accumulative TREND - when the lube sample is taken periodically from a component or system without a lube change. The test data values will be increasing with each sample, since the Time on the lube is increasing. This is normal for hydraulic systems and transmissions which use the same lube fill for a long span of time. All Test Data on a sample is relevant to: 1 - Time on the LUBE, how long in service? With time the lube is accumulating more and more and more. 2 - Time on the UNIT, how long in service? Each system has a lifespan and at each plateau there are differences. All VALUES on a TREND must be evaluated by these two Factors. Remember the amount of Make-up Lube added to a unit will affect the values on a Trend. 2
  3. 3. A TREND sets the stage for corrections to be made, to clean up and save before a DISASTER. It identifies the source of a problem and allows the corrections to be built around the cause. Too often only the obviously visual is repaired (the symptom) and the cause is not found. One lube sample, for troubleshooting or taken after a failure, does NOT show the history of how the condition developed or how long it has existed, ONLY a TREND can do this. With Failure Analysis it is very difficult to reconstruct what caused the problem. The test data for a lube sample sometimes will fail to support the problem or failure, when the analysis service is used as a ONE sample failure analysis. Using Monitor™ for ONE lube sample troubleshooting or failure analysis will, most of the time, provide a basic diagnostic picture of the condition that exists. At this point in time, a Lab Report is probably not required as the problem can be seen. By waiting to use Monitor™ until there is a problem or Failure, the True Value and Purpose has been lost. Trend Lube Analysis as a Preventive Maintenance Tool will give an Early Alert so corrections can be made to prevent a major disaster. Use Monitor™ to schedule maintenance and repair jobs, reduce repair times and cost, and increase equipment uptime and reliability. These periodic samples monitor the operating condition of the system from which CORRECT RESPONSE they were taken. The OBJECTIVE is an EARLY ALERT to an abnormal condition by a TO ABNORMAL significant change in the TREND. The correct Response to an abnormal report is: LAB REPORT 1st Perform maintenance or minor repairs to correct cause and resample again, at normal or half interval to monitor. 2nd Perform other diagnostic tests to confirm condition and possible cause of problem. A sudden and significant increase in wear rates or contamination level from a previous sample seldom indicates an impending disaster. Normally a minor repair correcting a maintenance oversight will return the next sample to normal. Disassembly of a component is not warranted on the basis of a lube analysis report only. There must be symptoms of a problem and/or other diagnosis performed which confirms the need for a disassembly. Remember to check how long the lube has been in service. Wear metals and contaminants accumulate with TIME, the longer the lube is in service, the more there will be. A lube and filter change is the first thing indicated when wear metals and/or contaminants are abnormal, especially when the recommended drain interval is near or has been exceeded. 3
  4. 4. ™ Monitor LUBE SAMPLING KITS Monitor™ is the most advanced lubricant diagnostic service offered as an equipment preventive maintenance program for the parts and service departments. Monitor™ Lubricant Analysis provides a report from an independent lab to evaluate component wear. BASIC ENGINE ANALYSIS - CC2525 This kit includes all tests necessary to evaluate engine wear and contamination for all types and makes of engines. This kit does not evaluate the condition of the lubricant itself. Tests include: • Spectro-Analysis of 24 metals • Fuel dilution • Soot Contamination • Percent of water contamination HYDRAULIC FLUID ANALYSIS - CC2527 This kit includes all tests necessary to evaluate component wear and contamination, lubricant condition and deterioration for all hydraulic systems, power shift and power shuttle transmissions. Tests include: • Spectro-Analysis of 24 metals • Percent of water contamination • Lube viscosity @ 100 C • Particle count per milliliter • Infrared Analysis (checks for amounts of nitration and oxidation of the lube) EXTENDED OIL DRAIN ANALYSIS - CC2543 This kit includes all tests necessary to evaluate engine wear and contamination for all types and makes of engines. This kit does evaluate the condition of the lubricant itself. Tests include: • Spectro-Analysis of 24 metals • Fuel dilution • Soot Contamination • Percent of water contamination o • Viscosity @ 100 C • Total Base Number or Total Acid Number 4
  5. 5. LUBE SAMPLING KITS (CONTINUED) ENGINE OIL ANALYSIS WITH ENGINE FAILURE ANALYSIS - CC2544 PRE-PAID MAILER - CC2528 This kit includes all tests necessary to evaluate This kit includes all tests necessary to evaluate component wear and contamination, lubricant engine wear and contamination for all types and condition and deterioration for engines and non- makes of engines. This kit does not evaluate the engines. condition of the lubricant itself. Tests include: Tests include: • Spectro-Analysis of 24 metals • Spectro-Analysis of 24 metals • Fuel dilution • Percent of water contamination • Soot Contamination • Lube viscosity @ 100 C • Percent of water contamination • Particle count per milliliter • Infrared Analysis (checks for amounts of nitration and oxidation of the lube) • Total Base Number or Total Acid Number • Analytical Ferography • Fuel dilution • Soot contamination Monitor™ like other TREND lube (oil) analysis services is designed to analyze REPRESENTATIVE USED lube samples to determine the condition of a component or system. As a LUBE SAMPLE lubricant flows through a component, it picks up and carries with it wear and contaminant particles. Therefore the lab can analyze a lube sample to determine if wear is normal or abnormal. A lube sample must be representative, timely and well-documented. • A good sample must be representative of the lube in service if the test data is to be meaningful. If sample cannot be taken during equipment operations, take the lube sample immediately after shutdown from a system which has been running at operating temperature for a period of time. This will insure the wear and dirt particles are suspended and not settled out, also that water or coolant has not separated from the lube. A lube sample taken from a cold system may be difficult to draw and invalid due to water condensation. A lube sample is normally drawn through a plastic tube and should be taken from the middle of a reservoir or sump to make sure it is representative. Sludge, dirt and water will collect on the bottom and sampling there will give the impression that the circulating lube is in poorer condition than it really is. Sample port in return line to filter is better. Always take sample from same point under similar conditions. • Since a lube sample indicates the condition of the component or system at the point in time it is taken, it is important to promptly send it for analysis. The longer the sample sits the less significant it becomes. 5
  6. 6. ™ Monitor LUBE SAMPLES • A sample must be fully documented with the Unit I.D., interval of time from previous sample, how long the unit has been in service, amount of make-up lube added, date sample was taken, type and grade of lube, operating conditions, and all the information requested on the Component Registration & Bottle Label. Only when a sample is representative, timely, and well documented can you be sure of getting the most value for your investment. Monitor™ lube analysis, as a scientific approach to maintenance management, is USED LUBE SAMPLES designed to analyze USED lube samples for wear metals and contaminants. The purpose of Monitor™ is to establish and monitor the typical wear rates of the component or system from which the lube samples are extracted. Monitor™ lab tests include only a minimum of the physical characteristics of a lube and do not evaluate any lubricant performance tests. Therefore, the Monitor™ lab cannot determine if a new lube sample is acceptable or correct for a given application. A New Lube Reference Sample is just that, and has only one purpose - comparison NEW LUBE to the test results of a USED lube sample. REFERENCE SAMPLE 1. To determine the possible source of some metals such as molybdenum, copper, silicon, etc., which may be in the new lube as an additive. 2. To evaluate what may have changed in the USED lube sample from the new lube. Component When a unit or component is being “sampled” for the first time, it is necessary to Identification complete and submit the enclosed registration form. Each component from each unit of equipment receives its own computer record. As lubricant samples are submitted, a permanent database record of evaluations is established for the unit or component (provided that multiple samples for each registered component are submitted during each twelve-month period). Therefore, proper component registration and regular samples are important in obtaining accurate “trend analysis” patterns. Equipment Since the Monitor™ lab is an independent laboratory, its expertise covers most makes and types of units and systems. Therefore, you can expect a thorough evaluation of most systems. Lube Data Check only the box for the component being sampled. ID slip only has mfr, model line, lube type and grade line for one component, therefore, only one component should be checked. A separate ID slip should be issued for each component or use F4 Form to submit all on one form. You may also pre-register components or systems on this unit which you intend to sample in the near future. The lube data requested is very important so the lab can accurately identify deterioration or improper lube mixing. Application Check only the box which best describes your usage of the unit being registered. This will assist in the evaluation of your lube sample as to how the working environment affects the unit and lube. Failure to give all the information requested limits the MonitorTM lab in their evaluation of your lube samples. 6
  7. 7. BOTTLE LABELS BEFORE taking the lube sample, fill in the information requested on the sample bottle label. The labels for the sample bottles are different for each of the four kits. The bottle label identifies the component or system the lube sample was taken from and the analysis tests to be performed. A. The Customer Name and Unit I.D. must always be the same on samples from the same unit and agree with the Component Identification form. B. The most important history information concerning your lube sample must be supplied on the bottle label of each sample: • Time on the LUBE, how long has the lube been in service? With time the lube is accumulating more and more wear particles and is deteriorating more. • Time on the UNIT, how long has the unit or component been in service? Each system has a lifespan and at each plateau there are differences. Example: A low value (PPM) with long hours = no or little concern. The same value (PPM) with low hours = could represent a PROBLEM. The accuracy of the Monitor™ lab’s evaluation depends greatly on these two factors: • Time on the LUBE (miles/hours since system drain) • Time on the UNIT (miles/hours on system) C. Sample data - all that is required is month and day (8/13) sample was taken from unit. Unit Sampled Before? - If this is the 1st sample sent to Monitor™ lab, check the box for NO; if previous samples have been sent to Monitor™ lab check the box for YES. Lube Changed at Sampling Time? - If the lube was changed after sample was taken, check the box for YES; if it was not changed, check the box for NO. D. Be sure to indicate the correct type of component or system the lube sample was taken from by checking the box. REMEMBER the detail and accuracy you use in the Component Identification form and Bottle Label will result in better detail and accuracy in the evaluation of your lube sample by the Monitor™ lab. The lab can analyze your lube sample and give you an opinion as to the unit’s basic condition without the complete information requested, however, it may be a very limited evaluation due to missing data. 7
  8. 8. ™ Monitor MONITOR REPORTS TM Lubricant Evaluation Results - all evaluations are based on repetitive sampling “trend analysis” and are reported direct to you generally within two working days from the date the sample is received. Typically, samples received in the morning are processed and evaluated with a report issued the next or following work day. If, in the opinion of laboratory, a questionable condition exists, they will contact you or your dealer by phone, fax or e-mail, thus the importance of completing your registration form and label attached to the lube container. The back side of the report includes graphs to help identify trends. 1 2 3 4 3 7 11 8 10 12 8
  9. 9. HOW TO READ THE REPORT Understanding a Monitor™ Lab Report is easy. FIRST determine the importance you should place on the report by the Severity Code status assigned. SECOND identify the unit by the ID number and the Unit Type for the component or system. THIRD read the laboratory’s recommendation and suggested actions in the Comment section, which are based on the test results. 1. SEVERITY CODE: **** Critical situation - Requires high degree of concern and immediate corrective action. *** Unsatisfactory condition - Requires corrective maintenance action very soon. ** Watch condition - Minimum degree of concern - May require some minor maintenance action or Watch to see what happens with next sample. * Satisfactory condition 2. UNIT I.D. Customer: Customer’s identity Location: Customer city/town Unit Type: Component name relating to sample Application: Equipment application MFR: Manufacturer or equipment Model: Identifies manufacturer’s model Lube MFR: Lube brand Type/Grade: Manufacturer’s lube type and grade This information comes from a completed ID Slip with first sample sent to Lab 3. COMMENT Comments by laboratory consultant on lube sample analyzed 4. LUBE SAMPLE HISTORY from Bottle Label (Information taken from bottle label) Sample Date: Date you removed the sample Lube: Inservice hours or miles Unit: Total operating hours or miles Make-up Lube: If any was added, and you reported Lab #: Number assigned to report by laboratory Report Date: Date report was printed 5. NAME AND ADDRESS of Monitor™ dealer to provide product and service support 6. FIRST COLUMN: Date sample was taken Date sample was received at laboratory SECOND COLUMN: Lube inservice hours or miles at time of sample Total unit operating hours or miles at time of sample 7. TEST DATA - lube analyzed in parts per million by weight related to wear metals, contaminant metals, additive metals, non-metallic contaminants, and lube data. 8. NOTE: - There is space provided to record laboratory analysis of 5 samples. When the 6th sample is submitted, it will be recorded on the last or 5th line on each report. The record entry for the first sample will be removed from the report. This process will continue each time a sample is submitted on the same unit or same component. 9
  10. 10. ™ Monitor HOW TO READ THE REPORT (CONTINUED) 10. DATE Column repeats sampled date and received data from (Area 6) CHG - was lube changed after sample was taken? N = NO, Y = YES, U = UNKNOWN NOTE: This information comes from Bottle Label 11. PC/ml = PARTICLE COUNT PER MILLILITER Particle count and micron sizing. Elevation and trend from previous samples with 4-6-10-14-21-38-70-100 micron size particles. 12. IR = Infrared Infrared reporting on oil condition. All reports are organized in the same format. The following illustration represents reporting. The Test reported are based on the kit purchased. 10
  11. 11. SAMPLING INSTRUCTIONS ENGINES: WHEN TO SAMPLE Just prior to oil drain - consult your equipment operator’s manual for change Interval recommendations. MECHANICAL TRANSMISSIONS, DIFFERENTIALS, FINAL DRIVE/PLANETARY: Just prior to oil drain, but at least every five hundred hours of operation, but not less than three times annually. HYDRAULIC SYSTEMS, POWERSHIFT TRANSMISSIONS: Just prior to oil drain, but a least every five hundred hours of operation, but no less than three times annually. IMPORTANT: WHERE TO SAMPLE Ensure that the system you are sampling has been well circulated in order to obtain a true representative sample. Dirt, system debris and water tend to settle out to the bottom of the reservoir, while light fuels tend to float on the lubricant. Take all lubricant samples immediately after shut-down for a representative test result. Always take samples in the same manner. WARNING: Clean all lubricant access areas prior to sampling. Assemble sampling tools and materials in a clean area. Follow these precautions to eliminate any contaminants from entering the sampling tools, bottle or system reservoir. To obtain engine oil sample, engine Engine must be at operating temperature. Draw lubricant samples through the dipstick retaining tube or sampling valve installed in filter return. Never take samples from a drain pan or a drain plug! Mechanical To obtain lubricant samples, Transmissions, the system must be at operating temperature. Differentials, Final Draw lubricant samples through oil level check- Drive/Planetary point or through dipstick retaining tube, whichever is provided. Consult your equipment Operator’s Manual for these locations. 11
  12. 12. ™ Monitor SAMPLING INSTRUCTIONS (CONTINUED) Hydraulic Systems To obtain hydraulic fluid sample, the system must be at operating temperature. Draw fluid sample through the oil fill port of the system reservoir. Ensure that the sample is drawn from the mid-level of the reservoir. Be sure the sample you take is a representative lube sample of the reservoir condition and is not being taken from the inside of a screen or filter element. (Example some Excavators). CAUTION: Some hydraulic reservoirs are pressurized. Relieve pressure before sampling. Engine should not be operated when a pressurized system is open. Consult your equipment operator’s manual for hydraulic system precaution. Powershift Transmission To obtain lubricant sample, the transmission must be at operating temperature. Draw lubricant sample from oil level plug, or through dipstick retaining tube, whichever is provided. Consult your equipment operator’s manual for this location. Final Drive Final Drives (For Equipment With Final Drive Lube Reservoir Independent From all Other Systems): Must be at operating temperature. Draw lubricant sample from oil level plug. Consult your equipment operator’s manual for this location. Any pressurized system may have a sampling port NOTE: installed in a return line if convenient for sampling. 12
  13. 13. HOW TO SAMPLE Carefully unpack contents of sampling kit. DETAILS FOR DRAWING Place material on a clean surface. LUBRICANT SAMPLES *Monitor™ Sample Kit does not include pump, QuickDraw, or tubing. CC2802 Vacuum Pump Complete the unit or component registration COMPLETE UNIT record form. It must be included with your initial REGISTRATION FORM lubricant sample. Complete the information AND BOTTLE LABEL requested on a sampling bottle. “CAP” the sample bottle with the sealing cap. CAP THE SAMPLE Place the sample in the safety shipping bottle. Clean and store the suction device for future use. COMPLETE THE Complete the mailing label return address and SHIPPING CARTON attach to mailer jar. Insert the lubricant sample andregistration form, affix appropriate first class postage and mail. If a critical condition is discovered, you or your dealer will be notified immediately by phone, fax or e-mail. 13
  14. 14. ™ Monitor TECHNICAL NOTES There are any number of metallic elements to be found in used lubes, SPECTROMETRIC but they can be generally grouped into four basic categories. METALS The product of friction, corrosion, and/or deterioration of components within a • Wear Metals: given unit: Metal Engines Transmissions Gears Hydraulics Iron Cylinder liners, Gears, Disks, Housing, Gears, Bearings Rods, Cylinders, Rings, Gears, Bearings, Brake Bands, Shaft, Housing Gears Crankshaft, Shaft Camshaft, Valve . Train, Oil Pump Gear, Wrist Pins Chrome Rings, Liners, Roller Bearings Roller Bearings Shaft Exhaust Valves, Shaft Plating, Stainless Steel Alloy Aluminum Pistons, Thrust Pumps, Thrust Washers Pumps, Bushings, Bearings, Turbo Thrust Washers Thrust Plates Bearings (Cat) Nickel Valve Plating, Steel Steel Alloy from Roller Steel Alloy from Alloy from Crankshaft, Bearings & Shafts Roller Bearings Camshaft, Gears from & Shafts heavy bunker type . diesel fuels Copper Lube Coolers, Bushings, Clutch Plate, Bushings, Bushings, Thrust Main & Rod Bearings, (Auto/Powershift) Lube Thrust Plates Plates, Lube Cooler Bushings, Turbo Coolers Bearings, Lube . Additive Lead Main & Rod Bearings, Bushings (Bronze Alloy), Bushings Bushings Bushings, lead Solder Lube Additive (Bronze Alloy), (Bronze Alloy) Supplement Grease Contamination Tin Piston Flashing, Bearing Cage Metal Bearing Cage Bearing Overlay, Metal, Lube Bronze Alloy, Babbit Additive metal along with Copper & Lead Cadmium N/A N/A N/A N/A Silver Wrist Pin Bushing Torrington N/A Silver Solder from (EMD’s), Silver Solder Needle Bearings Lube Coolers (From Lube Coolers) (Allison Transmissions) Titanium Gas Turbine N/A N/A N/A Bearings/hubs/ blades, Paint (White Lead) Vanadium From heavy bunker N/A N/A N/A type diesel fuel 14
  15. 15. Multisource Metals are Highly Dependent on the Application and Environment Abrasives, dirt; contaminated lube storage; casting sand or metal from • Contaminant Metals: manufacture; coolant additive metals, etc.: Metal Engines Transmissions Gears Hydraulics Silicon Dirt, Seals & , Dirt, Seals & Dirt, Seals & Dirt, Seals & Sealants Sealants Sealants Sealants Coolant Inhibitor, Coolant Inhibitor, Coolant Inhibitor Coolant Inhibitor Lube Additive Lube Additive Lube Additive Lube Additive (15 ppm or less) (15 ppm or less) (15 ppm or less) (15 ppm or less) Sodium Lube Additive, Lube Additive Lube Additive, Lube Additive, Coolant Inhibitor, Coolant Inhibitor, Coolant Inhibitor, Coolant Inhibitor Salt Water Salt Water Salt Water Salt Water Contamination, Contamination, Contamination, Contamination, Wash Detergents Wash Detergents Airborne Airborne Contaminant Contaminant Lithium Coolant Inhibitor, Coolant Inhibitor, Coolant Inhibitor, Coolant Inhibitor, Airborne Airborne Airborne Airborne Contaminant Contaminant Contaminant Contaminant • Multi-Source Metals: Metal Engines Transmissions Gears Hydraulics Boron Ring Plating, Lube Additive, Lube Additive, Lube Additive, Lube Additive, Coolant Inhibitor, Coolant Inhibitor, Coolant Inhibitor Coolant Inhibitor Grease Additive Antimony Lube Additive, Lube Additive Lube Additive, Lube Additive, Maganese Steel Alloy, Steel Alloy Steel Alloy, Steel Alloy Lithium N/A Lithium Complex Lithium Complex Lithium Complex Grease Grease Grease Metals placed in the lubricant by the blender to achieve beneficial effects: • Additive Metals: Metal Engines Transmissions Gears Hydraulics Magnesium Detergent Dispersant Detergent Dispersant Detergent Dispersant Detergent Dispersant Additive, Airborne Additive, Airborne Additive, Airborne Additive, Airborne contaminant contaminant contaminant contaminant Calcium Detergent Dispersant Detergent Dispersant Detergent Dispersant Detergent Dispersant Additive, Airborne Additive, Airborne Additive, Airborne Additive, Airborne contaminant, contaminant, contaminant, contaminant, Contaminant Contaminant Contaminant Contaminant from water from water from water from water Barium Lube Additive Lube Additive Lube Additive Lube Additive (rare) (rare) (rare) Phosphorus Anti-Wear Additive Anti-Wear Additive Anti-Wear Additive Anti-Wear Additive (ZDP) (ZDP) (ZDP) (ZDP) EP Additive EP Additive (Extreme Pressure) (Extreme Pressure) Zinc Anti-Wear Additive Anti-Wear Additive Anti-Wear Additive Anti-Wear Additive (ZDP) (ZDP) (ZDP) (ZDP) 15
  16. 16. ™ Monitor TECHNICAL NOTES (CONTINUED) It is necessary to monitor all of these metal types to fully evaluate a system. The situation is far from this simple, however, because every metal can at least fit into two categories, some into all three. Furthermore, there are not only engines to consider, but gears, compressors, hydraulics, and the same metals have different meanings in each of these subcategories. Even further complexities exist because different manufacturers utilize different metallurgies, oil companies different additives, and coolant additive manufacturers different materials. The case of SILICON is perhaps the most complex and interesting. It first may be found up to 15 ppm as silicone polymer defoamant. It may also be found as a major constituent of certain synthetic lubes. It is, of course, found as “dirt” or abrasives. It can be found as a constituent in certain preparatory agents used to lubricate or seal at manufacture. It can be found as a constituent in silicon rubber gaskets or seals. Finally, it can also be found in certain coolant additives - its presence in the lubricant might, therefore, be indicative of a coolant leak. In most situations, an experienced consultant can pin down the source of silicon to a single possibility by evaluating the remaining test data. Nearly everyone would like to know “limits” for metals, particularly the WEAR variety. It is the WEAR metals, in particular, however, which cannot be assigned GENERIC limits because every piece of equipment develops its own unique wear rate. For this reason chronological, cumulative histories are kept on each individual piece of equipment - in this way we can monitor WEAR RATE or, more precisely, the CHANGE IN WEAR RATE from sample to sample. We do use formulae for monitoring change in wear rates, but these are proprietary. They vary according to manufacturer, model and application among several other items. Make- up lube addition also plays a role in the wear metals concentrations derived. CONTAMINANT metals can be assigned loosely defined “rule-of-thumb” limits, but, once again, manufacturer and application influence our tolerances. ADDITIVE metals let us know a great deal about the nature of the additive package placed in the lube. We can usually identify the type of product in use and continue to monitor the quality control of that product as new batches are received. It is recommended that each batch of new lube be tested for spectrometric metals for a NOTE: baseline. We then monitor the additive metals for relative consistency from sample to sample, assuring customers that the correct lube is being utilized. Such baseline testing is recommended a minimum of every six months. SAE Paper #740535 Other References: Heavy Duty Equipment Maintenance/Management (June, July, August 1978) FUEL CONTAMINATION is a measurement of unburned fuel found in the FUEL CONTAMINATION crankcase/sump of liquid-fueled reciprocating engines (LFREs), although there are some specialized application for “fuel” detection. One example might be the desire to measure solvent thinning of hydraulic fluids. Another example would be to spot saturated (“wet”) gas engine fuel. Every LFRE will have a certain amount of raw fuel in its blow-by. Usually the heat of the engine evaporates volatile portions of this fuel at a rate producing an equilibrium (a stable level of fuel contamination). If an equilibrium is not reached, or too high an equilibrium percentage is maintained, there is a problem: leaking injectors, faulty carburetor floats, leaking injector seals, pumps or jumper lines, worn rings, etc. 16
  17. 17. In over-the-road (OTR) diesel applications, 1.5-2.0% or lower is typical. An pick-up- and-delivery (P & D) application features a much higher percentage of idle time, consequently the engine lube tends to remain too cool to evaporate fuel properly. Further, and particularly true of carbureted fuel systems, there is a distinct over-fueling condition at low idle speeds, which could also contribute to a higher fuel contamination level. In diesels, however, such contribution is usually negligible since fuel is more proportionately metered with injected vs. carbureted systems. Occasionally there will be units which consistently show fuel contamination levels above 4.0% owing to extremely concentrated P & D work. Under these circumstances no corrective action, short of altering the application in which the engine is used, will prevent such results. Excessive fuel contamination must be controlled because lube film strength decreases, adding to the risk of abnormal wear, particularly in the ring/cylinder region. There is also the distinct danger of a crankcase explosion at levels beyond 7%. The independent laboratory utilizes an FTIR (Fourier-Transform Infrared) Spectrometer to measure fuel contamination. Lubes and fuels both emanate from the same source: crude oil. Fuels are the more *Technical Point: volatile portion of the crude product. It is important to understand that fuel does not possess a distinct boiling temperature as does, for example, water, ethyl alcohol, acetone, for it is not a “pure” product or compound. It is a mixture of petroleum products within a boiling RANGE. A typical ASTM #2D diesel fuel might have an initial boiling temperature of 150° C at standard sea level atmospheric conditions, but as the product is carried over to the distilling receiver, the temperature required to boil the fuel continually increases. A typical ending temperature might be well over 300° C. ALL fuel contamination detection methods must necessarily be estimates of the TRUE fuel level. Other References: SAE paper #740535 Heavy Duty Equipment Maintenance/Management (June, July, August 1978) SOOT CONTAMINATION SOOT represents a measurement of Carbon Combustion By-Products in the lube system. Diesel Engine Soot develops from incomplete combustion and is blown past rings and valve guides as a normal operational process. It is finely divided carbon, oftentimes less than a micrometer in size and is the cause of routine lube blackening. Lube additive dispersants also play a role in lube blackening as they maintain much of the generated fuel soot in suspension rather than allow it to be filtered. Proper filtration helps control fuel soot, especially when particles combine with themselves (agglomerate) to form larger particles. 17
  18. 18. ™ Monitor TECHNICAL NOTES (CONTINUED) Sources of excessive soot in diesel systems include: 1. Over-fueling or restricted air intake 2. Poor injector spray pattern (plugged nozzle, etc.) 3. Worn rings, valve guides, turbocharger or supercharger seals 4. Oxidized fuel and lube products* (poor timing, poor fuel or lube) 5. Plugged or inoperative lube filters Usually recommendations are for corrective action or drains at or near 3.0% soot in most diesel systems, but the decision to render advice is also based on the unit’s pattern on an individual basis as well. It is recommended that samples be taken when a unit is at operating temperature, WATER or has been shut down for only a short while. As well as providing the most CONTAMINATION representative sample, it minimizes chances of obtaining samples with condensate water (unless there is a problem with systems using water traps). Water should not normally be found in most systems at levels above 0.1% (1000 ppm), provided samples are taken correctly.Oftentimes, the laboratory detects metallic coolant additives rather than water because the water is continually evaporated by a unit’s heat. When water is detected, these same metals aid in qualifying the source (coolant/condensate/etc.; salt or fresh water in marine situation). Exemplary Metals Chromium Silicon Sodium Boron Magnesium Phosphorus Possible Evaluation Combinations Washing Compound X X OR X (e.g. Truck Washrack) Salt Water or X Coolant Sea Water X X Chromate Coolant X X Treatment Coolant/Glycol X X Coolant/Glycol X X X Coolant/Glycol X X Other References: SAE Paper #740535 Heavy Duty Equipment Maintenance/Management (June, July, August 1978) 18
  19. 19. VISCOSITY OF A LUBRICANT IS A MEASURE OF ITS RESITANCE TO FLOW VISCOSITY WITH RESPECT TO TEMPERATURE. Two things are therefore necessary in reporting viscosity: a) temperature at which the viscosity is measured; b) the amount of time units for a given amount of the flow through a given passage. The two most common temperatures for motor oil viscosity are 40° C and 100° C (formerly 100° F and 210° F respectively). The units reported are CENTISTOKES, abbreviated cSt or cs . The change in viscosity temperatures is the result of an effort to standardize to a common world system; essentially it is metrication of the viscosity reporting system. VISCOSITY INDEX IS THE CHANGE IN RESISTANCE TO FLOW OF A LUBRICANT WITH RESPECT TO TEMPERATURE. As a lube is heated it will get “thinner” (its viscosity will decrease). The amount of thinning which takes place over a given temperature span can be expressed as VISCOSITY INDEX (VI), a term expressed as a number without units. The less tendency a lube has to thin with temperature increase, the greater is VI. Determination of VI requires two viscosities at different temperatures (usually 40° C and 100° C). SIGNIFICANCE OF VISCOSITY: There are numerous references which cite that the viscosity of a lube is its most important single property, and perhaps this is true, at least when the lube is new. By itself, however, a viscosity does not nearly qualify a lube. It basically defines the film thickness the lube will have for a given application. New lubes placed in engines or other machinery should be inspected for correct initial viscosity. Assuming no errors are made with the initial fill, the following factors can influence viscosity: Liquid fuel contamination Downward Non-emulsified water contamination Shearing of VI-improving polymers Wrong make-up lube addition Soot contamination Upward Certain emulsions with water Lube oxidation/degradation Wrong make-up addition Most modern lubes, particularly engine lubes, are “oxidation-stable” under standard drain intervals so that, unless extended drains are contemplated, it is better to observe the contamination which influences viscosity rather than the viscosity itself. It is possible to have combined contamination such that viscosity remains stable, but an abnormal situation exists (e.g. high fuel and solids). For this reason, the laboratory DOES NOT ROUTINELY DETERMINE VISCOSITY UNLESS EXTENDED DRAINS ARE CONTEMPLATED, for it has limited value in detecting fuel contamination and is oftentimes misleading. On the other hand, INCREASED VISCOSITY, IN THE ABSENCE OF FUEL OR OTHER CONTAMINATION, WILL USUALLY INDICATE LUBE OXIDATION/ DEGRADATION, and the viscosity is the most convenient means to measure this with reasonable effectiveness. VISCOSITY, along with neutralization number, SHOULD ALWAYS BE REQUIRED BY CUSTOMERS WISHING TO SAFELY EVALUATE EXTENDED LUBE DRAINS. 19
  20. 20. ™ Monitor TECHNICAL NOTES (CONTINUED) SAE Motor Oil Grade or Number Viscosity @ 100° C Standard SAE grading 20 Appx. 5.6-9.2 cs for MOTOR oils 30 Appx. 9.3-12.4 40 Appx. 12.5-16.2 50 Appx.16.3-21.8 It should be noted that 100° C is the ONLY temperature to be used in classifying motor lube by SAE grade. Also note that there are no MOTOR lube grades below 20 or above 60. There is also no such legitimate term as “weight” (e.g. “30 weight”). The “W” designations found on certain cans or drums refers to a -18° C viscosity requirement for the particular product, and should always be followed by a number (20, 30, 40, or 50) indicating the grading for 100° C. This pertains only to motor lubes. Gear lubes and specialty lubes have other systems for viscosity grading which do not necessarily relate to motor lubes. It is reasonable to expect a lube to increase at least one grade (e.g. 30 SAE to 40 SAE) during typical drain intervals. This occurs because of routine lube oxidation and the evaporation of more volatile constituents in the lube. Solids, of course, will also contribute.VI-improving polymers are synthesized materials which artificially thicken lubes as temperature increases. They exhibit this ability due to their physical form at various temperatures. At lower temperatures their molecules are very compressed, offering little resistance to lube flow. At elevated temperatures these molecules spread out to their full physical length, impeding flow, or “thickening” the lube. Shearing of these polymers is the actual cutting of the molecular chain into shorter chains, an action which can occur between two rubbing surfaces in the system. Heat also contributes to this phenomenon. In the shorter state these chains no longer impart a thickening effect to the lube, and the polymer is said to have been “sheared”. The lube, consequently, is more nearly as it was prior to polymer treatment and may then fail to have sufficient viscosity at operating temperature. Expected Ranges of Other Lubes MIN. cs. @ 100° C MAX. cs. @ 100° C ATF (automatic transmission fluids) 5.5 8.5 Hydraulic Fluids (typical tractors) 5.5-9.8 7.0-13.0 90 SAE Axle/Manual Transmission 13.5 23.9 140 SAE Axle/Manual Transmission 24.0 40.9 250 SAE Axle/Manual Transmission 43.0 77.0 SAE paper #740535 Other References: Heavy Duty Equipment Maintenance/Management (June, July, August 1978) A motor lube consists of two major parts: BASE STOCK (or BASE “OIL”) and ADDITIVES ADDITIVE. The BASE STOCK is the primary lubricant and can be petroleum or synthetic. The ADDITIVE is usually a laboratory or synthesized product, or combination of products, which enhances the BASE STOCK’S performance. Together the BASE STOCK and ADDITIVE make up the “finished lubricant”. Usually the ADDITIVE comprises less than 20% of the total lubricant volume, but there are not absolute limitations. A lube is qualified primarily by its performance not its additive quantities. Furthermore, the BASE STOCK is equally important to a lube’s performance. 20
  21. 21. Its chemical structure, resistance to oxidation, wax content, etc. are all critical factors, as well as its compatibility with the proposed additive package. As the name implies, these compounds help maintain engine cleanliness by Detergents preventing deposits on critical areas such as ring lands, or by removing such deposits. They also help maintain deposits such as fuel soot in suspension to be filtered out or drained with the lube. Metallic carriers are generally used (except where “ashless” lubes are required) to bring the non-metallic portion, which is the “detergent” part of the compound, to the lube. The metal, however, is also beneficial in itself for its alkaline, acting as a neutralizer for corrosive acids, thus helping to give the lube its Total Base Number. Dispersants have overlapping properties with detergents, in that they, too, maintain Dispersants particles in suspension. Many technical people distinguish the two terms by calling metallic particle suspenders “detergents” and totally non-metallic (ashless) particle suspenders “dispersants”. They reduce the tendency of small particles to combine into larger particles, taking some of the burden off the filters, and prevent deposition of these particles on valve covers and moving parts particularly at low temperatures. Monitor™ soot test aids in monitoring the effectiveness of the lube’s dispersants. This material, usually a silicon polymer, acts in a very complex chemical and Defoamant physical manner to minimize foaming tendencies of lubes. It has limited solubility in lubricants of a non-silicon nature, and this limited solubility helps its effectiveness in accelerating the formation of large bubbles from small ones which dissipate from the lube much more readily. The larger bubbles rise to the surface quickly and then break. There are antioxidants for fuels and lubricants, and most of them are non-metallic. Anti-Oxidants Oxidation is a general term used to describe the combing process with oxygen which a lubricant tends to do. This, in turn, forms undesirable compounds which are far less suitable as lubricants. A number of metals, most notably copper, tend to aid (catalyze) oxidation. Some types of antioxidants, therefore, react chemically with the offending metal to nullify its catalytic effect. Another way to inhibit oxidation is to break the chemical chain by “sacrificing” the antioxidant. This type of compound has a great affinity for oxygen when it appears in oxidation products and can combine with it to form harmless compounds, while simultaneously stopping the oxidation chain. Anti-Corrosives These materials prevent chemical corrosion from occurring. They can accomplish this by forming a chemical, protective coating on metal surfaces, or they can directly attack and neutralize materials (usually acids) which cause corrosion. EP agents increase the load carrying ability or film strength of lubes. This in turn Extreme Pressure prevents or at least minimizes direct metal-to-metal contact. Many gear systems need (EP) Agents lubes fortified with EP agents to function properly. Some EP agents include sulfurized sperm oils and molybdenum sulfide. These materials are similar in scope to EP agents; some plate or coat while some Anti-Wear Additives combine chemically with metal surfaces, particularly ferrous (iron or steel), to form a protective coating, necessary in the event that the lube film is interrupted. VI improvers (See pages 19 and 20) consist of polymers whose properties change Viscosity Index significantly with temperature, such that a lubricant resists “thinning out” as its temperature (VI) Improvers increases. Polyisobutylenes were among the early compounds used. The latest technology uses copolymer chemistry, which seems to be far more stable, particularly for use in diesel engines. A VI improver’s function is to enable one to experience much-improved cold starting capabilities while retaining necessary film thickness at operating temperature. 21
  22. 22. ™ Monitor TECHNICAL NOTES (CONTINUED) The pour point of a lube is simply the lowest temperature at which it will still Pour Point Depressants pour. The amount of wax in a lube influences its pour point. Pour point depressants minimize the size of wax crystals formed in the lube. By so doing, they allow the lubricant to achieve its lowest possible pour point, based on its true viscosity characteristics and not on its wax content. Polymethacrylates are the general class of organic compounds used as pour point depressants, also providing some VI improvement. The above are only a portion of the various additives developed for petroleum products, but they represent most of the important ones for automotive use. It should also be noted that several of the above properties can, at times, be fulfilled adequately by a single additive compound. NOTE: ADDITIVES, with the exception of solid lubricants, are SOLUBLE in BASE STOCKS and would normally not be susceptible to filtration depletion from typical automotive filters. It is possible, however, that in the course of being consumed, an additive could form an insoluble product capable of being filtered. * The laboratory uses industry-standard terminology for synthetic lubricants: products which consist of base stocks manufactured by chemical synthesis and containing necessary performance additives. ICP spectrometers routinely measure five potential additive metals: Magnesium Additive Metals (Mg), Calcium (Ca), Barium (Ba), Phosphorus (P), and Zinc (Zn). NOTE: Boron (B) and Sodium (Na) may also be additives, as well as Molybdenum (Mo), though less frequently. These metals are detected to aid in verifying the correct product is being used, but detection of metals alone cannot verify their continued effectiveness as an additive. The reason is very simple: when a spectrometer measures Ca, for example, it is measuring Ca in ANY form (additive or contaminant). When the Ca-containing additive is placed in the lubricant, it has a particular chemical structure and one cannot monitor that structure or its effectiveness with metals detection alone. In analyzing a NEW LUBE, however, any Ca measured is fresh, active additive, and this information helps predict the lube’s performance capabilities. Detergent Carriers Ca, Mg and Ba, in order of current use frequency, are the most common metals in use as carriers. Typically only one of these three metals is found in a specific brand and type of motor lube, dependent on how the suppliers choose to meet the desired specification. It is possible, however, to find new lubes using a combination of metals to achieve the same purpose. There is no rule. These metals impart alkaline properties to the lubricant, enabling it to neutralize corrosive acids. Mg has the highest alkalinity per given weight amount, Ba the least. For this reason Mg and Ca are nearly exclusively found in high performance motor lubes with sulfated ash limitations. Anti-Wear/Anti-Oxidants Zinc dithiophosphate, containing P and Zn in roughly equal proportions, is the most common anti-wear/antioxidant compound found in motor lubes and many hydraulic oils, thus is routinely investigated for its presence. There are several types of zinc dithiophosphates, each having its own favorable properties for particular applications. 22
  23. 23. Zinc dithiophosphate is an additive which provides multi-function capability. In the anti-oxidant role it can break the oxidation chain of a lubricant; in the anti- wear role it chemically “plates” out on such components as cams and lifters, or gears and serves as a lubricant in the event that metal-to-metal contact takes place. Inasmuch as some Zn and P plate-out, a decrease in these elements might be expected, but make-up lube, as with all additives, tends to restore the level and maintain equilibrium. It is possible to find lubes having P without Zn used as an anti-wear agent. There are a number of other metals which are used as additives. Molybdenum (Mo) as molybdenum sulfide is a solid lubricant currently enjoying some popularity as an extreme pressure agent. Unlike most additives, however, it is not dissolved in the base lube, but suspended as minute particles less than one micron in size. It should be pointed out that when Mo is used as an additive, detection of Mo to evaluate Mo-coated rings is not possible, again due to the lack of distinction between one form of a metal and another by emission spectrometric analysis. Similarly if Zn is an additive, Zn from brass or bronze is masked. If leaded gasoline is an engine’s fuel, lead cannot be used to evaluate potential bearing wear. New lubes should be tested for base data to avoid misinterpretation as to the source of a metal. Most motor oils will have Mg, Ca and/or Ba from 500-3500 ppm, dependent “Typical” Levels on the specification*. Lubes with high alkaline properties may have anywhere from 5000-8000 ppm Mg+Ca+Ba. Many industrial fluids have no metallic additives. P and Zn are generally found from 600-1500 ppm. Automotive gasoline and several diesel engines usually require a minimum of 1000 ppm zinc dithiophosphate for valve train protection, as this is the area of highest “unit” loading in such systems. *Automatic transmission fluids may have similar levels, however, not necessarily normal. The most common defoamant in use is a silicone polymer. It is usually added at Defoamants the ppm level, thus it is not unusual to see up to 12 ppm silicon in new lubes, although 7-8 ppm is a typical range. Testing the new lube is important, for additional Silicon from the starting level will usually indicate abrasives (“dirt”). Molybdenum, usually as a sulfide, is used as a friction reducer or EP agent in Other Metals certain specialty lubes. Levels of nearly 1% (10,000 ppm) are not unusual. Boron tends to be found co-existing with Mg additives at up to 4% of the Mg value. Similarly, sodium may be found in the presence of Ca or Ba. There are exceptions to these guidelines. Other References: SAE Paper #740535 Heavy Duty Equipment Maintenance/Management (June, July, August 1978) There are a variety of neutralization numbers utilized in the petroleum industry. NEUTRALIZATION This discussion is confined to the two most commonly used versions. NUMBERS 23
  24. 24. ™ Monitor TECHNICAL NOTES (CONTINUED) Simply stated, TAN IS THE TOTAL AMOUNT OF ACID AND ACID-ACTING TOTAL ACID NUMBER CONSTITUENTS FOUND IN THE LUBE. The term “acid” does not necessarily (TAN) connote metal-corroding materials themselves. Many chemicals, including necessarylube additives, can have an acid number. SIGNIFICANCE: Increases in TAN of used lubes from the starting point of the new lube (which may NOT necessarily be zero) usually indicate LUBE OXIDATION or CORROSIVE ACID CONTAMINATION. “OXIDATION” is a general term used to describe the degradation of the basic lube product as a result of operating temperatures and/or churning with air. Generally, oil thickening is associated with oxidation. Organic acids are formed prior to and during thickening which can be detected by TAN increase. Oxidation of lube is not only significant from the standpoint of thickening, but the lubricating quality (lubricity) of the lube itself can also be reduced. CORROSIVE ACID is formed primarily from sulfur blow-by products in the combustion process. Any amount of water contributes toward activating this acid to the point of parts corrosion. The formation of corrosive acids in engines is unavoidable, but alkaline (basic) materials are added to motor lubes to counteract the acid upon entry into the crankcase. Corrosive acid in non-engine systems is usually an environmental problem. One exception is the formation of corrosive hydrochloric acid in refrigeration systems, where freon deterioration may occur in the presence of moisture. There are no “typical” TANs, but it is fairly unusual to observe one above 10.0 - an increase of 2-3 above starting point may be unacceptable. The change in TAN is the concept to monitor. TOTAL BASE NUMBER TBN IS THE AMOUNT OF ALKALINE MATERIAL (generally as corrosive acid (TBN) neutralizers) IN THE LUBE, commonly referred to as ALKALINE RESERVE. SIGNIFICANCE: TBN IS OF PRIMARY CONCERN IN MOTOR LUBES, as additives are placed in the lube when it is blended to neutralize corrosive sulfur acids formed in the crankcase in the normal process of combustion. Measurement of TBN allows one to know if the starting additive package is still capable of counteracting combustion acids. Therefore, TBN IS AN ESSENTIAL ELEMENT TO THE SAFE EVALUATION OF LUBE DRAIN INTERVALS. Generally a new lube starts with the highest TBN it will exhibit. From that point TBN will tend to decrease as acids consume its alkaline properties. The addition of fresh make-up lube, however, helps forestall the decline in TBN, oftentimes, allowing (all other factors being equal) extension of lube drains in properly maintained engines. This will naturally vary from unit to unit dependent upon individual conditions. Typical motor lubes have TBNs of 5-7. “Highly-compounded” oils may have TBNs 12-15. Marine oils using high-sulfur fuel may have TBNs of 35-40, while upper cylinder lubricants in those same engines may exceed 70 TBN. NOTE: TBN alone is not a relative indicator of lube quality, only its ability to neutralize corrosive acids. A higher TBN clearly demonstrates better capability to counteract acids, but does not mean the higher TBN lube is better than, or even equal to, a lower TBN lube with respect to other important properties. It should also be noted that most of all motor lubes can have both a TAN and TBN in 24
  25. 25. the new and used state. If one regards these terms as two distinctly different properties, there is no difficulty in explaining their simultaneous presence. Ideally one would perform analyses for both terms in the inspection of motor lubes, but TBN is by far the more important property of the two for motor lubes. TAN is usually acceptable when TBN is sufficient. TAN is almost exclusively used for non-engine systems because there is no combustion process taking place and because many non-alkaline lubes are in use in such systems, making the analysis for TBN pointless. TAN also applies for large stationary 2-cycle gas engines using “mineral oil” type lube. A WORD ABOUT pH - pH and TAN are oftentimes confused. The concepts are quite involved but, succinctly, pH is relative acid strength while TAN is total amount with no regard for strength. Weak acids, such as lube oxidation products, do not significantly affect pH. SAE paper #740535 Other References: Heavy Duty Equipment Maintenance/Management (June, July, August 1978) Today nearly every lubricants user is concerned about costs and availability of DRAIN INTERVAL product and disposal of used product. EVALUATION The lube analysis consulting industry is ideally situated to evaluate drain intervals, enabling one to minimize lubes consumption, but with reasonable safety, as opposed to arbitrary drain interval, which can lead to problems whose costs far exceed the lubes “savings”. Monitor™ lab introduced the “HYBRID” concept in evaluating drain intervals. The principle of the “HYBRID” concept is to place the units to be evaluated on a drain interval analytical program, monitoring lube DEGRADATION, as opposed to only WEAR and CONTAMINATION. Once the safe lube drain limit is determined, one can then abandon the drain interval analytical program, returning to the more economical wear/contamination. The purpose of this is twofold: 1) Arriving at a maximum SAFE drain interval ECONOMICALLY for a given lube, system type and application; 2) Monitor the unit to be certain no excessive contamination (and subsequent wear) develops within the system prior to lube change. The “HYBRID” system presupposes that a uniform lube change interval will be adopted for a given class of units. It is important to understand that varying “SAFE” drain intervals are attainable dependent upon the equipment manufacturer. (For discussion purpose, use of a specific lube product will be assumed.) If one has a “mixed” equipment set, be it engines, gears, hydraulics or other, one should consider each manufacturer separately. Generally at least half a dozen units of each manufacturer and application should be evaluated thoroughly prior to adopting a drain interval “across-the-board”. Naturally, the larger the test group used, the greater will be the confidence level of the drain interval projections. 25
  26. 26. ™ Monitor TECHNICAL NOTES (CONTINUED) THE ULTIMATE The concept of extending drain intervals to achieve optium oil drain intervals is only viable APPROACH TO using a fluid and unit condition monitoring program such as the monitor oil analysis kit part CONSERVATION CC2543. By monitoring both the fluid condition and the unit’s condition, it is possible to determine at what hour/miles interval you can extend the oil life to without sacrificing life expectancy. This can be done by monitoring the oils TBN (Total Base Number or Reserve Alkalinity). Typical engine oil’s TBN will start around 8.0 to 10.0. As the oil ages, the TBN decreases to a point where the oil no longer has the alkalinity to neutralize acids that form from the combustion process. Through testing you can determine how far to let the TBN drop before the wear metals start to increase. The scattergram graph depicts the typical decline of the TBN as the hours/miles increase. Using the graph and monitoring and comparing the wear metals patterns of the engine will give the analyst the information needed to determine the “Optimum Oil Drain Interval.” This determination could only be proved if every unit in the system were sampled (once again manufacturer and application may dictate a sub-system approach). Because scheduling of routine maintenance becomes far more complex when there is a variety of manufacturers and applications, some firms change lubes purely “on condition”, i.e., only when lab analysis suggests it. This would further require that every unit be regularly tested using a drain interval evaluation analytical package. The minimum drain interval evaluation test recommended is: SPECTRO METALS FUEL CONTAMINATION (liquid-fueled recips only) FUEL SOOT (LFRE) WATER VISCOSITY NEUTRALIZATION NUMBER If pure SYNTHETICS are in use, infrared analysis is also useful to detect standard petroleum product contamination of the synthetic. Monitor™ Kit CC2543 Lube Analysis includes these tests. 26
  27. 27. 1. LUBE CONSUMPTION: FACTORS INFLUENCING All other things being equal, the greater the lube consumption, the better the chances DRAIN INTERVALS* for extended drain. In effect, the lube is being renewed or “sweetened”, including beneficial additives. 2. LUBE QUALITY: Some lubes are simply more effective than others for particular applications, whether due to better base stock or to superior additives. 3. HEAT: Excessive temperature is an enemy of all lubes, promoting oxidation and other forms of lube degradation. 4. CONTAMINATION: Excessive contaminants will ultimately render a product ineffective as a lubricant. Type and degree of filtration can influence this area, dependent on the nature and cause of the contamination. 5. How a particular piece of equipment is used plays an important role in lube drain interval and affects all of the above parameters. *This list excludes the situations where a unit has a serious mechanical problem. SAE paper #740535 Other References: Heavy Duty Equipment Maintenance/Management (June, July, August 1978) PARTICLE COUNTING “Particle Counting” is a term denoting the detection of a particulate matter in a fluid with respect to size range and quantity. There are a number of methods for particle counting. The earliest counts were centered around microscopy, wherein filter patch samples were prepared and then viewed under a microscope with a calibrated grid for sizing. A manual count within grids was then conducted. The process, while certainly useful, is nevertheless tedious and relatively slow by today’s standards. Particle counting instrumentation includes techniques like light scattering, which is currently the most popular method for inspecting petroleum products. One instrument type causes a thin diameter flow through a sensor-monitored light path. Another utilizes a laser that is rotated to describe a one ml. cylinder in a static sample in the path of the last beam and its sensor. Particle counting is becoming a popular analytical method for particulate monitoring in non-opaque fluids. Some of the specific applications include: Automatic Transmissions Gas Reciprocating Engines Coolants Gas Turbines Compressors Hydraulics Diesel Fuels New Lube QC Filter Evaluation Refrigeration Systems NOTE: IF A PRODUCT SAMPLE OF TWO INCH THICKNESS WILL NOT PASS LIGHT TO THE NAKED EYE TO ANY REASONABLE DETECTABLE SIGNIFICANCE, IT IS PROBABLY TOO OPAQUE TO YIELD A RELIABLE PARTICLE COUNT BY LIGHT SCATTERING METHODS. 27
  28. 28. ™ Monitor TECHNICAL NOTES (CONTINUED) The micrometer (also called “micron”) is the particle measurement standard unit. It is one-millionth of a meter. Results are usually expressed in particles per milliliter, or particles per 100 milliliters. Commonly requested ranges: A B Greater than 25 microns 5-10 microns Greater than 15 microns 10-25 microns Greater than 30 microns 25-50 microns Greater than 50 microns 50-100 microns 100+ NOTE: 40 MICRONS IS THE THRESHOLD OF PARTICLE DETECTION IN THE AVERAGE NAKED EYE. IT IS DOUBTFUL WHETHER MEASUREMENT OF METALLIC PARTICLES ABOVE 100 MICRONS IS USEFUL, FOR THEY TEND TO SETTLE QUITE RAPIDLY DUE TO THEIR DENSITY, AND RELIABLE COUNTS ARE DIFFICULT TO ACHIEVE. There are some sophisticated techniques for taking lube samples for particle counting, Sampling but these techniques are almost impossible to achieve in a field environment. For field monitoring, therefore, we recommend VERY CONSISTENT observation of the standard sampling methods one would use for lube. The laboratory’s regular sampling jars are “reasonably clean” and are factory-capped to minimize contamination from the container. Some Limitations of 1. As mentioned earlier, samples too opaque will simply not pass enough light to Particle Counting allow the sensor to react. 2. Water oftentimes is not differentiated from true particulates, particularly when the water is finely dispersed. Samples with known water, therefore, are normally not amenable to particle counting. 3. Samples which are too “dirty” tend to interfere with the ability of the sensor to properly discriminate. The result is unreliable data. Certainly it is always possible to dilute “dirty” samples with filtered solvent until a count is technically feasible, but extremely high dilution can lead to significant errors once the dilution factor is applied. 4. Particle counters do not care about the compositional nature of particles— only their size and quantity. Unless one is simply making counts for relative purposes, therefore, one will need other tests to help suggest the composition/ source of the particulates. While samples are not always representative, the following discussion is Evaluation Particle conducted on the premise one is evaluating reasonably good data. Counts Particle counts are best viewed on a relative basis just like the rest of the tests run on lubes for maintenance diagnostics. They should also be viewed in conjunction with other test data, again on a relative basis. As an example, if wear metals rise with particle count, there is an obvious connection. The question might be, however, is the apparent wear FROM the particles, or do the particles simply REFLECT the increased wear metals? One 28

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